<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<style>
    .a1{
        width: 140px;
        height: 140px;
        padding: 20px;
        border: 10px solid #000000;
        background-color: gold;
        text-align: center;
word-wrap: break-word;
       /* 字母数字自动换行 */
    }
</style>
<body>
    <div class="a1">
        qqqqqqqqqqqqqqqqqqqqqqqqqqqqqqq
    </div>
</body>
</html>